BACKGROUND AND OBJECTIVES: Technology has allowed for the production of fine needles which decrease headache incidence, but increase technical difficulties and failure rates. This study aimed at prospectively evaluating technical difficulties and incidence of failures and headaches in patients submitted to spinal anesthesia with 27G, 29G Quincke and 27G Whitacre needles. METHODS: Participated in this study 300 patients, aged below 50 years, submitted to spinal anesthesia with the aid of an introducer (20G 1¼), who were divided into three groups, according to needle type and gauge: GI (27G Quincke), GII (29G Quincke) and Glll (27G Whitacre). Technical difficulties and failure rates were evaluated in the operating room. Postoperative headache was evaluated until hospital discharge. Headache patients were treated with analgesics, hydration and, if needed, epidural blood patch. RESULTS: There were no significant differences in technical difficulties, failure rate and headache. Total headache incidence was 1.6%, always mild and of short duration, without the need for epidural blood patch. CONCLUSIONS: In the conditions of this study, 27G, 29G Quincke and 27G Whitacre needles have neither influenced the incidence of headache or spinal block failure nor puncture difficulties.